That's a nice little boozer, but with central London prices, and an equivalent annual salary of £30k, I'd be inclined to forego the fish-finger sandwich, and sneak a home-made sarnie instead. The pint of Directors is a given.
Lesley’s link shows that this is a 4-month contract.
Nice venue, albeit the “staff canteen” is at the Royal Society. But you can get a nice fish-finger sandwich, and a pint of Directors, at the Two Chairmen.